Correspondence
Dr. Khaled S. Aseri
Department of Family and Community
Medicine, King Saud bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City P.O. Box 9515, Jeddah 21423
Saudi Arabia
e-M: [email protected] Submission: 03 Nov. 2019 Accepted: 29 Dec. 2019 Citation
Aseri KS, Mulla AA, Alwaraq RM, Bahannan RJ.
Characterizing occupational low back pain among surgeons working in Ministry of Health hospitals in Jeddah city: prevalence, clinical features and risk and protective factors. JKAU Med Sci 2019; 26 (2): 19-34. DOI: 10.4197/
Med.26-2.3
Copyright: ©Th e Author(s), YEAR. Publisher. Th e Journal of King Abdualziz University - Medical Sciences is an Offi cial Publication of
“King Abdulaziz University”. It is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permit unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Characterizing Occupational Low Back Pain among Surgeons Working in Ministry of
Health Hospitals in Jeddah City: Prevalence, Clinical Features, Risk, and Protective
Factors
Khaled S. Aseri
1,
CMAB, Abeer A. Mulla
2,
MBBS, Raghda M. Alwaraq
3,
MBBS, Raneen J. Bahannan
2,
MBBS1King Abdulaziz Medical City, Jeddah, King Saud bin Abdulaziz University for Health Sciences, Medical College Department of Family and Community Medicine, Jeddah, Saudi Arabia
2Faculty of Medicine, Ibn Sina National College for Medical Studies, Jeddah, Saudi Arabia
3Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
Abstract
A cross-sectional study was conducted to investigate the prevalence as well as the determinants and clinical features of occupational low back pain among surgeons working at Ministry of Health hospitals in Jeddah, Saudi Arabia by exploring its history combined with time of onset after starting the operating room work and self-appraisal of the relationship with the surgical work. Factors and predictors such as professional, socio-demographic and lifestyle factors, medical history, etc. were collected and analyzed. Two hundred and sixteen surgeons (69.9% males, mean age 39.03 years, median work: 5.00 years) responded. Prevalence of occupational low back pain was 55.8% (95% CI: 49.0%, 62.3%); high rates of inadequate management and self-treatment had a notable impact on all 4 domains. Multivariate regression showed two independent protective factors (regular physical exercise [OR = 0.27, P = 0.002] and back health education [OR
= 0.41, P = 0.031] and two independent risk factors (high exposure to risky activities [OR = 1.06, P = 0.048] and presence of chronic pain other than back pain [OR = 2.59, P = 0.012]). More than one in two surgeons are likely to suff er from occupational low back pain. The protective roles of regular physical activity and back health education are highlighted.
Keywords
Occupational; Low back pain; Surgeons; Prevalence; Impact; Risk Factors; Prevention; Education
Introduction
T
he worldwide prevalence of chronic low back pain (LBP) was estimated between 4.2% and 25.4%depending on the population characteristics, region and age category[ 1]; with up to 42% reported point and lifetime prevalence[ 2 ,3]. Besides these disturbing epidemiological pictures, LBP has a major eff ect on social and professional activities since the functional capacity of the individual is restricted by pain; thus, it represents a signifi cant cause of absenteeism[ 4].
Focusing on the healthcare workers, LBP is an annoying problem that could aff ect the work process.
In a recent prospective study conducted in France, approximately one-quarter of the healthcare workers with LBP did not return to their regular work during a 2-year follow-up period[ 5]. Estimates show that 47%-70%
of healthcare workers had LBP, with a point-prevalence of 30%[ 6 ,7]. In Kingdom of Saudi Arabia (KSA), a recent study conducted in the Eastern Region concluded that the majority of Saudi healthcare workers complain of LBP once in their lives with a prevalence of 79%; most were work-related [ 8].
On the other hand, approximately 4 out of 10 cases of LBP are attributed to occupational exposures [ 9]. Several work activities and professional circumstances have been identifi ed as precursors for LBP, which makes occupational LBP (OLBP) a distinct entity.
Among the community of healthcare workers, surgeons are particularly vulnerable to experiencing OLBP compared to other specialties [ 6]. Studies showed that 70%-85% of surgeons complained from LBP in their lifetime [ 10, 1 1]. Furthermore, chronic LBP among surgeons would eventually lead to signifi cant impairments in work performance, which may aff ect the quality of patient’s care and surgical outcomes and induce considerable healthcare costs, besides the substantial impact on the surgeon’s quality of life [ 12].
However, several studies conducted among surgeons did not explore the occupational nature of LBP, which may lead to misinterpretations of the presented epidemiological pictures and confusions with non-occupational LBP that may be pre-existing or due to extra-occupational etiology such as trauma, sport injuries, etc. Thus, identifying OLBP among surgeons would provide more accurate evaluation of the back-health risks related to the surgical profession,
which would enable establishing more specifi c correlations with the work environment risk factors and protective measures.
The authors wanted to investigate the prevalence and clinical characteristics of OLBP among surgeons working in healthcare institutions of the Ministry of Health (MOH) in Jeddah, Saudi Arabia; as well as to identify eventual independent risk or protective factors of an occupational or extra-occupational nature.
Methods Population and Setting
This cross-sectional study involved surgeons working at fi ve MOH hospitals in Jeddah, Saudi Arabia, including King Fahad General Hospital, King Abdul-Aziz Hospital and Oncology Center, Al Thagher Hospital, King Abdullah Medical Complex, and East Jeddah Hospital.
Inclusion criteria applied for both gender and all nationality and age category residents, board-certifi ed specialists and consultants in surgery. All surgical subspecialties were included, while other operatory room staff was not included. This study was approved by the Directorate of Health Aff airs, MOH, Jeddah;
and researchers received relevant authorizations from all participating hospitals’ directors and surgery departments’ heads to collect the data specifi ed in the study protocol.
Sampling
Sample size was calculated to detect 70% prevalence of low back pain[10] among a fi nite population of 503 surgeons working in the participating centers, with a 95% confi dence interval, 80% statistical power, and 5%
type I error. The calculated sample size was N = 197.
A convenience sampling technique was used to include all eligible participants until reaching the target sample size, with respect of a proportional allocation by hospital as per the respective number of surgeons.
Data Collection Tool
This study used a semi-structured questionnaire that was designed by the authors, comprising a modifi ed version of a validated questionnaire published in a previous study by Bin Homaid et al. [ 10] that aimed to explore operatory room risk activities (ORRA) among operatory room staff in Makkah, Saudi Arabia. The
questionnaire included the following nine parts: 1) Professional data: hospital name, subspecialty, years of experience, and work years; 2) Socio-demographic data: age, gender, marital status, etc.; 3) Lifestyle factors: smoking, physical exercise, hobbies, etc.; 4) Past medical history: specifi c back history (back trauma, surgery, injury, etc.), other medical and surgical history (other surgery, other trauma, co-morbidities, etc.); 5) Physical and psychological stress at work: perceived level of stress, hours of standing, hours of sitting, etc.;
6) ORRA, which explored surgeons’ exposure to 8 diff erent activities/postures (e.g. lifting, transferring, or pulling patients/objects) during a routine work time, as adapted from study by Bin Homaid et al. [ 10] and that was modifi ed by using a 5-point Likert type frequency scale (from never = 0, to very frequently = 4); 7) OLBP assessment, which was carried out by exploring history of LBP in addition to 2 discriminative criteria including time of onset (before vs after starting the operating room job) and self-appraisal of the relationship of LBP with the surgical work; 8) OLBP characteristics: pain severity, frequency and evolution pattern over the last 12 months, care-seeking behavior, etiology and diagnosis, and management; 9) Self-reported impact of OLBP on 4 dimensions including professional achievement, social relationships, psychological well- being, and activities of daily life.
After face- and content-validation of the questionnaire, an electronic version was adapted and published in an online survey platform and the related Uniform Resource Locator (URL) was obtained.
Data Collection Method
First, the online questionnaire URL was diff used via group messaging, by adding all phone numbers of all surgeons; these were provided beforehand by the hospitals’ human resource administrators upon authorization of the respective directors and head managers. The questionnaire URL was accompanied with a short message soliciting for participation in the study and presenting its aim and relevance. However, due to the very low response rate (5.2%), the researchers called each surgeon individually and reiterated the call for participation by presenting the importance of the study in a persuasive and constructive debate. The study URL was closed on 14 March 2019 after reaching 216 participants.
Statistical methods
Statistical analysis was performed with the IBM SPSS Statistics for Windows, Version 21 (IBM Corp., Armonk, NY USA). The prevalence of OLBP was calculated as the percentage of surgeons who declared having LBP with onset after start of operatory room work (to exclude anterior symptoms) and being fairly associated to the profession as per the participant’s subjective judgment on a Likert-type probability scale (to exclude extra- occupational etiology). Results are presented with a 95% confi dence interval. Descriptive statistics were used to present socio-demographic, professional, lifestyle factors and job-associated stressors, in addition to OLBP characteristics and multidimensional impact. Categorical variables were presented as frequency and percentage, while numerical variables were presented as mean ± Standard Deviation (SD) for normally distributed variables and median (centile) for non-normally distributed ones. Regarding risky activities, an ORRA score (ORRAS) was calculated as the sum of the eight items’ scores to indicate the overall level of exposure (ORRAS range = 0, 32). The internal consistency of related parts of the questionnaire was assessed by calculating Cronbach’s alpha. Analysis of factors associated with OLBP used chi-squared test or Fisher’s exact test for categorical variables, as appropriate, independent t-test for normally distributed and Mann-Whitney U test for non-normally distributed ones. Multivariate binary logistic regression was carried out to analyze independent risk factors of OLBP by including all statistically signifi cant factors;
results were presented as odds-ratio (OR) with 95%
confi dence interval (95% CI). A p value of < 0.05 was considered to reject the null hypothesis.
Results
Participants’ Demographic and Professional Characteristics
Two hundred and sixteen surgeons responded to the questionnaire, 69.9% males, mean (SD) age of 39.03 (9.82) years and 78.3% were married. Of the participants, 32.7% were residents, 33.2% board- certifi ed specialists, and 34.1% were consultants, with median (P90) experience of 10.00 (25.00) years; with sub Table 1).
Participants’ Lifestyle and Clinical Characteristics
Of the total participants, active smoking was present among 28.3% with a median (P90) duration of 9.0 (20.0) years of smoking and an average of 5 (20) cigarettes per day. Other lifestyle characteristics showed low rates of regular exercise (36.3%) and hobbies and extra- professional activities (21.7%). Back history showed 16.8% of back injury in various circumstances including trauma (8.0%), sport injury (4.0), surgery (1.8%), or other causes (8.8%). Other medical data were characterized by high prevalence of overweight (35.8%) and obesity
(36.3%), with remarkably low medical history of hypertension (12.4%) and type II diabetes (5.3%) (Table 2).
Physical and Psychological Stress at Work A majority of the surgeons declared undergoing high (40.7%) or very high (15.9%) levels of stress during their work. The median (P90) average standing and sitting hours in a workday were 9.00 (20.00) and 5.00 (20.00) hours, respectively. Regarding operatory room risky activities (ORRA), the most frequently performed activities were lifting objects above the
Parameter Category Frequency Percentage Socio-demographic data
Gender Male 158 69.9%
Female 68 30.1%
Age (Years) Mean, SD 39.03 9.82%
Marital Status Single 42 18.6%
Married 177 78.3%
Divorced 5 2.2%
Widowed 2 0.9%
No. children None 59 26.1%
1-2 69 30.5%
3+ 80 35.4%
Professional data
Hospital Al Thagher Hospital 25 11.1%
East Jeddah Hospital 42 18.6%
King Abdul-Aziz Hospital and Oncology Center 64 28.3%
King Abdullah Medical Complex 28 12.4%
King Fahad General Hospital 67 29.6%
Degree Consultant 77 34.1%
Resident 74 32.7%
Board-certified specialist 75 33.2%
Years of experience Median, P90 10.00 25.00 Subspecialty Bariatric 6 2.7%
Breast Oncology/Surgery 5 2.2%
General Surgery 81 35.8%
Orthopedic 25 11.1%
Obstetrics/Gynecology 18 8.0%
Otolaryngology 14 6.2%
Pediatric Surgery 3 1.3%
Neurosurgery 5 2.2%
Urology 22 9.7%
Maxillofacial 17 7.5%
Plastic Surgery 8 3.5%
Surgical Oncology 2 0.9%
Gynecological Oncology 7 3.1%
Other (Specified) 13 5.8%
Years of work Median, P90 5.00 20.00 Because of missing data, all frequencies do not sum up to the total. Values are frequency/percentage, except if otherwise specified. P90: 90th centile; other sub-specialties included: ophthalmology (3), thoracic surgery (3), vascular surgery (2), colorectal surgery (2), anesthesia (1), gastroenterology endoscopic surgery (1), and gynecology and infertility (1).
Table 1. Participants’ demographic and professional characteristics.
Parameter Category Frequency Percent Lifestyle data
Home-job transportation mean Drive own car 147 65.0%
Private driver 52 23.0%
By taxi 8 3.5%
On foot 19 8.4%
Smoking Never 134 59.3%
Ever 92 40.7%
Previously 27 11.9%
Currently 64 28.3%
Type Cigarettes 55 24.3%
Shisha 36 15.9%
Smoking duration Median, P90 9.00 20.00 No. cigarettes per day Median, P90 5.00 20.00
Regular physical exercise No 75 33.2%
Yes 151 66.8%
Weekly exercise frequency Median, SD 3.00 6.00
Exercise (3 categories) None 75 33.2%
Irregular (< 3 times/week) 69 30.5%
Regular (≥ 3 times/week) 82 36.3%
Hobbies and extra-professional activities No 177 78.3%
Yes 49 21.7%
Holidays and travel Always 101 44.7%
Often 92 40.7%
Rarely 30 13.3%
Never 3 1.3%
Medical data
Height (cm) Mean, SD 169.80 9.42 Weight (kg) Mean, SD 83.25 20.23 BMI (kg/m2) Mean, SD 28.75 5.91 BMI categories (kg/m2) Underweight (< 18.5) 1 0.4%
Normal (18.5-< 25) 62 27.4%
Overweight (25-< 30) 81 35.8%
Class I obesity (30-< 35) 51 22.6%
Class II obesity (35-< 40) 20 8.8%
Class III obesity (40+) 11 4.9%
Current pregnancy No 64 28.3%
Yes 4 1.8%
N/A (males) 158 69.9%
History of back injury Never 188 83.2%
Ever § 38 16.8%
Trauma 18 8.0%
Sport injury 9 4.0%
Surgery 4 1.8%
Other 20 8.8%
Other surgical history No 151 66.8%
Yes 75 33.2%
Other trauma history No 175 77.4%
Yes 51 22.6%
Other medical history No 156 69.0%
Yes 70 31.0%
Hypertension 28 12.4%
Type II diabetes 12 5.3%
B.A or allergic rhinitis 13 5.8%
Other 24 10.6%
Because of missing data, all frequencies do not sum up to the total. Values are frequency/percentage, except if otherwise specified. P90: 90th centile; § a participant may have more than one injury; other medical history included hypothyroidism (7 cases), coronary artery disease (2), hyperlipidemia (3), hyperprolactinemia (2), migraine (2), anemia (1), atrial fibrillation (1), gout (1), hyperthyroidism (1), rheumatological disease (1), simple renal cyst (1), and thrombophilia A (1), in addition to two unspecified cases.
Table 2. Participants’ lifestyle and clinical characteristics
Parameter Level Frequency Percent
Stress level at work Low 10 4.4%
Moderate 88 38.9%
High 92 40.7%
Very high 36 15.9%
Average standing hours per workday Median, P90 9.00 20.00 Average sitting hours per workday Median, P90 5.00 20.00 ORRA
Lifting objects above the waist Never 22 9.7%
Rarely 63 27.9%
Occasionally 72 31.9%
Frequently 57 25.2%
Very frequently 12 5.3%
Rotating torso while bearing weight Never 58 25.7%
Rarely 75 33.2%
Occasionally 60 26.5%
Frequently 27 11.9%
Very frequently 6 2.7%
Bending to lift an item from floor level Never 40 17.7%
Rarely 67 29.6%
Occasionally 60 26.5%
Frequently 39 17.3%
Very frequently 20 8.8%
Transferring a patient from bed to chair/chair to bed Never 42 18.6%
Rarely 70 31.0%
Occasionally 54 23.9%
Frequently 50 22.1%
Very frequently 10 4.4%
Transferring a patient onto a stretcher Never 50 22.1%
Rarely 67 29.6%
Occasionally 47 20.8%
Frequently 51 22.6%
Very frequently 11 4.9%
Ambulating a patient Never 72 31.9%
Rarely 87 38.5%
Occasionally 45 19.9%
Frequently 19 8.4%
Very frequently 3 1.3%
Pulling a patient up the bed Never 41 18.1%
Rarely 96 42.5%
Occasionally 52 23.0%
Frequently 30 13.3%
Very frequently 7 3.1%
Repositioning a patient in bed Never 35 15.5%
Rarely 91 40.3%
Occasionally 62 27.4%
Frequently 29 12.8%
Very frequently 9 4.0%
Education/ information received on how to protect back and prevent LBP?
No 125 55.3%
Yes, but inadequate 55 24.3%
Yes, adequate 46 20.4%
Because of missing data, all frequencies do not sum up to the total. Values are frequency/percentage, except if otherwise specified. P90: 90th centile; OR: operating room risky activities; LBP: low back pain;
operatory room risk activities levels: Never, Rarely: 1-2 times per month, Occasionally: 1-2 times per week, Frequently: several times per week, Very frequently: daily
Table 3. Assessment of physical and psychological stress at work among surgeons
waist, transferring a patient from bed to chair/chair to bed and transferring a patient onto a stretcher. Further, only 44.7% reported having received information/
education on how to protect their back and prevent LBP and only 20.4% deemed the education received as adequate (Table 3).
Analysis of ORRAS showed mean = 12, SD = 6.30 and median = 12, and study of the distribution showed Kolmogorov-Smirnov test (statistics = 0.083, p = 0.001) and Shapiro-Wilk test (statistics = 0.984, p = 0.012), indicating that the variable is not normally distributed.
Internal consistency analysis of the ORRA scale including the eight items showed Cronbach’s alpha = 0.868, indicating a high reliability of the subscale.
Characterization of OLBP
History of LBP was reported in 192 of the total surgeons, indicating a prevalence of 85.0% (95% CI = 79.6%, 89.4%). Of the 192 surgeons, 156 surgeons (69.0% of the total surgeons) declared that their LBP fi rst occurred after starting their OR activity and 150 (66.4%) believed it is probably, very probably or defi nitely related to their job; which results in 126 having both criteria and more likelihood of having OLBP (prevalence [95% CI] = 55.8% [49.0%, 62.3%]).
Findings of clinical characteristics of OLBP are depicted in Table 4. These revealed that 32.5% of the
affl icted surgeons consulted a physician for their OLBP and 25.4% underwent an MRI or CT-scan; and the proposed etiological diagnoses were muscular injury or dysfunction (20.6%), discopathy (14.3%), degenerative disease (4.0%), sacroiliitis (1.6%) and functional LBP without any anatomical lesion (4.8%); whereas 54.8%
of the cases remained without diagnosis. Yearly frequency of OLBP episodes ranged between 0 to 300+
episodes per year (median = 6, P90 = 33), with the latest episode occurring in the past few days among 38.1% of the cases. Severity of the pain showed mean (SD) pain score = 5.01 (1.84) for the latest episode and 6.45 (2.18) for the most painful episode. Regarding management, rest (48.4%), NSAIDs (27.6%) and physiotherapy (26.6%) were the most frequently used options; however, opioid analgesics have been used by 2.6% of the affl icted surgeons (Fig. 1). Regarding the impact on life domains, OLBP yielded great impact on professional achievement, social relationships, ADLs and psychological well-being in 13.5%, 5.6%, 12.7% and 24.6% of the cases, respectively; while a moderate impact was reported among 33.3% to 40.5%
depending on the domain (Table 4).
Factors Associated with OLBP
Demographic and professional factors associated with OLBP as well as lifestyle and clinical factors are depicted in Table 5. No statistically signifi cant association of OLBP was found with any of the investigated demographic
Figure 1. Management options used among surgeons who declared ever experiencing low back pain (N = 192) Bars represent the percentage of surgeons of who already used the given management option among those who declared having ever had low back pain. A participant may use more than one option. Other management options included massage and physiotherapy (5 cases), stretching or exercise (4), weight reduction (1) and behavioral change (1)
Parameter Category Frequency Percent Consulted a physician No 85 67.5%
Yes 41 32.5%
Had MRI and or CT-scan No 94 74.6%
Yes 32 25.4%
Diagnosis / etiology Discopathy 18 14.3%
Muscular 26 20.6%
Degenerative 5 4.0%
Sacroiliitis 2 1.6%
Non-specific / Functional 6 4.8%
Unknown / Not Specified 69 54.8%
In your opinion, is your LBP related to your job? No not related 0 0.0%
Probably not 0 0.0%
Possibly 0 0.0%
Probably 36 28.6%
Very probably 31 24.6%
Definitely 59 46.8%
No. episodes past year Median, P90 6 33 Latest episode time > 3 months 21 16.7%
1-3 months 21 16.7%
1 week - 1 month 36 28.6%
A few days ago 48 38.1%
Evolution pattern Decreasing 31 24.6%
By intermittent peaks 60 47.6%
Constant intensity 27 21.4%
Increasing 8 6.3%
Latest episode severity Mean, SD 5.01 1.84 Most painful episode severity Mean, SD 6.45 2.18 Usual Management Nothing (wait until it passes away) 14 11.1%
Rest 57 45.2%
Self-medication 46 36.5%
I see a physician/specialist 3 2.4%
Other, specify 6 4.8%
Chronic pain in other area No 70 55.6%
Yes 56 44.4%
Impact of LBP
Job achievement Not at all 13 10.3%
Very little 46 36.5%
Somewhat 50 39.7%
To a great extent 17 13.5%
Social relationships Not at all 23 18.3%
Very little 45 35.7%
Somewhat 51 40.5%
To a great extent 7 5.6%
Activities of daily life Not at all 17 13.5%
Very little 42 33.3%
Somewhat 51 40.5%
To a great extent 16 12.7%
Psychological wellbeing Not at all 11 8.7%
Very little 42 33.3%
Somewhat 42 33.3%
To a great extent 31 24.6%
Values are frequency/percentage, except if otherwise specified. P90: 90th centile; SD: Standard deviation; LBP: Low back pain; OLBP: Occupational low back pain; OLBP criteria: 1= LBP first occurred after starting the OR job, 2=LBP described by the participant as being probably related to job, 3= LBP first occurred after starting OR job and described by participant as being probably related
Table 4. Characteristics and impact of occupational low back pain among affl icted surgeons (N=126)
Table 5. Demographic, professional, lifestyle and clinical factors associated with occupational low back pain among surgeons
Parameter Category
OLBP
P-value No (N = 100) Yes (N = 126)
Frequency Percent Frequency Percent Socio-demographic factors
Gender Male 72 45.6% 86 54.4% 0 Female 28 41.2% 40 58.8% 0.542 Age (years) Mean, SD 39.24 10.54 38.86 9.25% 0.772t Marital Status Single 19 45.2% 23 54.8% 0
Married 78 44.1% 99 55.9% 0 Divorced 1 20.0% 4 80.0% 0 Widowed 2 100.0% 0 0.0% 0.292 No. children None 26 44.1% 33 55.9% 0
1-2 32 46.4% 37 53.6% 0
3+ 35 43.8% 45 56.3% 0.943 Professional factors
Degree Consultant 36 46.8% 41 53.2% 0 Resident 36 48.6% 38 51.4% 0 Board-certified specialist 28 37.3% 47 62.7% 0.328
Years of experience Median, P90 9.00 27.70% 10.50 25.00% 0.475M Subspecialty Bariatric 3 50.0% 3 50.0% 0
Breast oncology/surgery 3 60.0% 2 40.0% 0 General surgery 34 42.0% 47 58.0% 0
Orthopedic 11 44.0% 14 56.0% 0 Ob-gyne 5 27.8% 13 72.2% 0
ENT 6 42.9% 8 57.1% 0
Pediatric surg. 3 100.0% 0 0.0% 0
Neurosurgery 3 60.0% 2 40.0% 0 Urology 6 27.3% 16 72.7% 0 Maxillofacial 11 64.7% 6 35.3% 0 Plastic surgery 4 50.0% 4 50.0% 0
Surgical oncologist 1 50.0% 1 50.0% 0 Gynecological oncology 3 42.9% 4 57.1% 0 Other (specified) 7 53.8% 6 46.2% 0.440 Years of work Median, P90 5.00 19.90% 6.00 20.60% 0.080 M Lifestyle factors
Home-job transportation mean Drive own car 64 43.5% 83 56.5% 0 Private driver 21 40.4% 31 59.6% 0 By taxi 5 62.5% 3 37.5% 0 On foot 10 52.6% 9 47.4% 0.579
Smoking Never 61 45.5% 73 54.5% 0 Ever: 39 42.4% 53 57.6% 0.642
Previously 11 40.7% 16 59.3% 0
Currently 28 43.8% 36 56.3% 0.791
Type Cigarettes 24 43.6% 31 56.4% 0 Shisha 15 41.7% 21 58.3% 0.853 Smoking duration Median, P90 10.00 18.80% 9.00 20.0% 0.967M
No. cigarettes per day Median, P90 10.00 20.0% 5 20.0% 0.641 M
Regular physical exercise No 23 30.7% 52 69.3% 0 Yes 77 51.0% 74 49.0% 0.004*
Exercise (times/week) None 23 30.7% 52 69.3% 0 Irregular 29 42.0% 40 58.0% 0 Regular 48 58.5% 34 41.5% 0.002*
Table 5. Demographic, professional, lifestyle and clinical factors associated with occupational low back pain among surgeons- -(CONTINUED)
Parameter Category
OLBP
P-value No (N = 100) Yes (N = 126)
Frequency Percent Frequency Percent Hobbies and extra-professional
activities
No 76 42.9% 101 57.1% 0 Yes 24 49.0% 25 51.0% 0.451 Holidays and travel Always 43 42.6% 58 57.3% 0
Often 43 46.7% 49 53.3% 0 Rarely 14 46.7% 16 53.3% 0 Never 0 0.0% 3 100.0% 0.424 Clinical factor
Height (cm) Mean, SD 169.51 9,99% 170,03 8,98% 0.680t Weight (kg) Mean, SD 83.86 22.32% 82.76 18.48% 0.686 t BMI (kg/m2) Mean, SD 29.05 6.45% 28.52 5.47% 0.506 t
History of any back injury Never 79 42.0% 109 58.0% 0 Ever § 21 55.3% 17 44.7% 0.134 Back trauma No 88 42.3% 120 57.7% 0
Yes 12 66.7% 6 33.3% 0.046*
Back sport injury No 93 42.9% 124 57.1% 0 Yes 7 77.8% 2 22.2% 0.081F
Back surgery No 99 44.6% 123 55.4% 0 Yes 1 25.0% 3 75.0% 0.632F
Other back injury No 91 44.2% 115 55.8% 0 Yes 9 45.0% 11 55.0% 0.943 Other surgical history No 66 43.7% 85 56.3% 0
Yes 34 45.3% 41 54.7% 0.817 Other trauma history No 84 48.0% 91 52.0% 0
Yes 16 31.4% 35 68.6% 0.035*
Other chronic pain history No 50 41.7% 70 58.3% 0 Yes 16 22.2% 56 77.8% 0.006*
Other medical history No 77 49.4% 79 50.6% 0 Yes 23 32.9% 47 67.1% 0.021*
Physical and psychological stress at work
Perceived-stress level at work Low 6 60.0% 4 40.0% 0 Moderate 43 48.9% 45 51.1% 0 High 40 43.5% 52 56.5% 0 Very high 11 30.6% 25 69.4% 0.210 Average standing hours per workday Median, P90 5.00 8.0% 6.00 8.0% 0.057 Average sitting hours per workday Median, P90 3.00 5.90% 2.50 4.0% 0.051 ORRAS Mean, SD 11.02 6.43% 12.98 6.08% 0.020*t
Received education to prevent LBP No 48 38.4% 77 61.6% 0 Yes, but inadequate 32 58.2% 23 41.8% 0 Yes, adequate 20 43.5% 26 56.5% 0.048*
Because of missing data, all frequencies do not sum up to the total. Values are frequency/percentage, except if otherwise specified. P90: 90th centile; ORRAS: operatory room risky activities score.
*statistically significant result (P<0.050); test used: MMann-Whitney U test, tindependent t-test, FFisher’s exact test, otherwise: chi-square test
Predictor Level OR 95% CI P-value Exercise (times/week) None Ref 0 0 0.004*
Irregular 0.73 0.31 1.73 0.470 Regular 0.27 0.12 0.61 0.002*
Other trauma history Yes 1.60 0.72 3.56 0.251 Other medical history Yes 1.04 0.50 2.18 0.912 Other chronic pain Yes 2.59 1.23 5.43 0.012*
ORRAS Score 1.06 1.00 1.12 0.048*
Education received No Ref 0 0 0.054*
Inadequate 0.41 0.19 0.92 0.031*
Adequate 1.21 0.51 2.89 0.669 OR: Odd ratio; CI: confidence interval; Ref: level used as reference category for the regression model; * statistically significant result (P <0.05).
Table 6. Predictors of occupational low back pain among surgeons (multivariate binary logistic regression)
and professional factors including gender, age, marital status, degree, years of experience or years of work, etc. Regarding lifestyle, the prevalence of OLBP was highest among surgeons who practiced no physical exercise (69.3%) and decreased to 58.0% and 41.5%
among those who practiced exercise irregularly and regularly, respectively, and the comparison is statistically signifi cant (p = 0.002). Paradoxically, history of back trauma was associated with lower prevalence of OLBP (33.3% versus 57.7%, P = 0.046); while history of sport injury (P = 0.081), surgery (p = 0.632), or other injuries (P = 0.943) of the back showed no signifi cant association with OLBP. On the other hand, history of other trauma (68.6% versus 52.0%, P = 0.035), other chronic pain (77.8% versus 58.3%, P = 0.006), and other medical history (67.1% versus 50.6%, P = 0.021) were signifi cantly associated with a higher prevalence of OLBP, compared to absence of these conditions, respectively.
Analysis of psychological stress showed no diff erence in the prevalence of OLBP between the diff erent levels of perceived stress at work (p = 0.210);
however, ORRAS was greater in the group of surgeons with OLBP (mean [SD] = 12.98 [6.08]) compared to their counterparts (mean [SD] = 11.02 [6.43]) and the diff erence was statistically signifi cant (p = 0.020).
Education to prevent LBP was associated with lower prevalence of OLBP compared to no education (P = 0.048); however, the group of surgeons who declared that the education they received was adequate exhibited relatively higher prevalence (56.5% versus 41.8%) compared to those who declared that the received education was inadequate (Table 5).
Independent Risk Factors of OLBP
Multivariate regression model including signifi cant factors from the previous analysis showed two
protective factors and two risk factors for OLBP. The two independent protective factors were regular physical exercise (OR = 0.27, P = 0.002) and education received that is deemed inadequate by the participant (OR = 0.41, P = 0.031). The two independent risk factors were ORRAS score (OR = 1.06, P = 0.048) and the presence of another chronic pain other than the back pain (OR = 2.59, P = 0.012) (Table 6).
Discussion Summary of Findings
Performing surgical procedures is a psychologically and physically demanding task, and prolonged discomfort or stress of the surgeons may diminish their operatory skills and compromise their career path.
Further, chronic and disabling pain resulting from an occupational disease not only impairs the quality of work life but also aff ects the overall quality of life of the individual. This study used a double-criterion method to estimate the prevalence of OLBP among surgeons and investigated the associated occupational and extra-occupational factors and predictors. According to the fi ndings, more than one in two (55.8%) surgeons suff er from OLBP; which was defi ned as a LBP that fi rst occurred after starting operating room job activity (criterion 1) with high likelihood of being related to job as per the participant’s judgment (criterion 2).
Estimation of OLBP: a Methodological Issue To date, there is no objective and reliable medical standard to discriminate OLBP from non-occupational LBP; as in many cases occupational and extra- occupational factors interlock or build up. Furthermore, occupational factors may only trigger silent preexisting abnormalities [ 13].
In the present study, use of the fi rst criterion aimed at providing a timing-based objective benchmark for OLBP to discriminate it from non-occupational LBP, which reduced the number of cases (prevalence) from 192 (85.0%) to 156 (69.0%). The use of the second criterion, which relied on the participant’s appraisal of the relationship between his / her LBP and professional activity, enabled the exclusion of 42 cases with low likelihood of OLBP. Crossing the two criteria aimed at reducing subjectivity in participant’s appraisal and lead to excluding 24 cases described as likely being related to occupation, although symptoms onset occurred before starting OR job. Although this method may have some limitations in diagnosis, it could be considered for screening purposes.
Prevalence of OLBP
In literature, the prevalence of OLBP shows great variation depending on profession and or population, as well as on criteria used to defi ne the outcome. For the present study, the profession and population was surgeons, while the outcome was the work-life prevalence of OLBP. Consistent with the fi ndings, prevalence of LBP among surgeons were remarkably high in literature. For example, in Iran, the point prevalence of LBP among surgeons was reported to be 39.9%, while 1-year prevalence was 71.7% and lifetime prevalence was 84.8% [ 11]; however, the estimates included both occupational and non-occupational, which explains the higher rates compared to the present study. Rates of LBP are also high among operatory room staff similar to the fi ndings from the studies conducted Bin Homaid et al. [ 10], where LBP was found to be as high as 74.2% [ 10], or that in Riyadh, showing 67% [ 14].
Although these rates are likely to be higher than common LBP in general population, they fall well within the range of estimates reported among healthcare workers, where the prevalence of LBP ranged between 47% and 74% [ 13,15,16]. Nevertheless, comparison between diff erent specialties points towards a higher risk among surgical positions, as evidenced by a study among healthcare workers in Saudi Aramco that showed a signifi cantly increased risk of back pain among surgeons with a remarkable odds ratio of 5.6 [ 17]. Similar evidence was reported in a study showing a rate of 65.7% for LBP among nurses working at a tertiary care hospital in Jeddah; working in surgical departments was associated with the greatest risk (OR = 2.2) of LBP compared to other departments and by reference to medicine [ 6]. This indicates that
the operating room working environment comprises specifi c harm that should be identifi ed and corrected.
Care Seeking Behavior: a Specifi c Issue
Assessment of OLBP characteristics showed inadequate care-seeking behavior among surgeons as only one in three of those affl icted have already sought medical advice regarding their OLBP and only one in four have benefi ted from imaging investigations. This results in a majority of cases (54.8%) being undiagnosed and probably being inadequately managed and followed up. A meta-analysis showed that health care-seeking behavior among individuals with chronic LBP is mainly determined by the level of disability; while other factors such as being female or having a history of back pain may also be associated with higher rates of care seeking [ 18]. In the present study, cases with disabling LBP are probably excluded from the population and can be considered biased, as only practicing surgeons were included while those on sick leave or unfi t for work were not surveyed.
Professional and Psychosocial Impact of OLBP Despite the low rates of care seeking among surgeons with OLBP, this study shows evidence of a signifi cant impact on affl icted surgeons’ quality of life as up to 25%
of them declared suff ering great impact and up to 40%
a moderate impact on various life domains including professional achievement, social relationships, psychological well-being and ADLs. Individuals with chronic LBP generally report poorer perceived health status, decreased quality of life, higher incidence of psychological distress and severe bodily pain than the general population which is frequently associated with constraints in professional and social achievement [ 19]. To Reduce Physical Stress in Operatory Rooms Unhealthy ergonomic conditions are a well-known characteristic of operating rooms, where surgeons are exposed to several tasks involving uncomfortable movements and postures, such as lifting, bending, twisting, etc. This is recognized to increase the risk of musculoskeletal disorders among surgeons as well as other operatory room workers, compared to their peers from other departments [ 20]. The present study examined the association of eight non-ergonomic movements and postures with OLBP among surgeons, using a scoring model based on the frequency of performing each activity. According to this model, a one-unit increment of the overall score (ORRAS)
is associated with a 6% odd risk of LBP (OR = 1.06).
This denotes a probable cumulative eff ect of non- ergonomic activities; besides eventual specifi c eff ects of each risky activity, which will be explored further and presented in another paper.
Role of Back Pain Education
In the present study, having received education to prevent LBP was an independent protective factor against LBP as it reduced the risk by 59%; however, this was only observed among participants who deemed the education as being inadequate. Although this result may seem paradoxical, it may be explained by surgeons who have more frequently experienced LBP being more demanding regarding back education issues. Otherwise, the eff ectiveness of back education and the relatively recent concept of “back school” in reducing disability and pain among patients with chronic low back pain is thoroughly demonstrated [ 21]. It was further demonstrated that back school programs contribute in improving quality of life and reducing the psychological impact of LBP [ 22]. From another view, adapting operating rooms by modern and ergonomic standards and equipment may reduce considerably the physical stress [ 23].
Regular Physical Activity as a Protective Factor for OLBP
Among the remarkable fi ndings in the present study, regular physical activity being signifi cantly associated with lower prevalence of OLBP was found to be an independent protective factor with approximately 73%
less risk (OR = 0.27) with reference to the absence of physical activity. On the other hand, irregular exercise was not demonstrated to reduce OLBP in this study. A systematic review and meta-analysis of 36 prospective cohort studies including 158,475 individuals demonstrated that leisure time physical exercise reduced signifi cantly the risk of chronic LBP by 11% to 16% (OR = 0.89 to 0.84) in a dose-dependent fashion with exercise frequency and intensity [ 24]. Further, moderate to high leisure time exercise constitutes a protective factor against sciatica and lumbar radicular pain, as evidenced by another meta-analysis carried out by the same authors [ 25]. On the other hand, it may be hypothesized that intensive physical activity may have detrimental eff ects on the back and increase the risk of chronic LBP; however, a prospective Norwegian study
including 9,616 women and 8,452 men without LBP at baseline confi rmed the benefi cial eff ect of physical activity at all intensity levels without evidencing a U-shaped relationship between physical activity intensity and LBP [26]. Additionally, there is extensive evidence supporting the benefi cial eff ect of exercise and physical activity in reducing pain and disability and improving psychological and physical well-being of individuals with chronic back pain, while highlighting the detrimental eff ects of inactivity in delaying return to normal activity and exacerbating disability and sick leave due to LBP [ 27]. Therefore, many instances, such as the Royal College of General Practitioners (UK), recommended various physical activities and exercise such as aerobic, muscle strengthening, stretching and postural control among patients with nonspecifi c LBP, with emphasis on structured exercise programs [ 28]. Economically, a randomized controlled trial demonstrated that eff ective exercise among individuals with nonspecifi c LBP was associated with a yearly cost savings of approximately US$3,200 by patient, compared to normal care, besides a notable gain in quality of life [ 29]. This highlights the importance of promoting physical exercise among the doctors’
community and more specifi cally surgeons. Medical schools and hospitals should endorse regular physical activity among students, residents and practitioners as a preventive measure to reduce the risk of OLBP and other occupational diseases and improve overall physicians’ health within a strategic vision to optimize care quality.
Conclusion
This current study used a double-criterion method to estimate the prevalence of OLBP among Saudi surgeons and found that more than one (55.8%) in two surgeons suff ered from this condition. Frequent exposure to intra- occupational risky activities is signifi cantly predictive of OLBP, which demonstrates that the operating room working environment comprises specifi c harm that should be further identifi ed and corrected.
Further, chronic and disabling pain resulting from an occupational disease not only impairs the quality of work life but also impacts the overall quality of life of the individual. On the other hand, fi ndings of this study highlight the protective role of regular physical activity as well as the benefi cial eff ect of back pain education, which indicates the relevance of promoting a healthy lifestyle and ergonomic working conditions.
Confl ict of Interest
The authors have no confl ict of interest.
Disclosure
The authors did not receive any type of commercial support either in forms of compensation or fi nancial for this study. The authors have no fi nancial interest in any of the products or devices, or drugs mentioned in this article.
Ethical Approval
The study design was reviewed and approved by the Unit of Biomedical Ethics Research Committee at King Abdulaziz University.
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